Process of forming hologram and polymeric holographic recording medium with sensitizer

Abstract

A new class of sensitizers for photopolymerizable compositions is disclosed derived from cyclic ketones and tricyclic aminoaldehydes. A preferred compound is cyclopentanone, 2.5-bis[(2,3,6,7-tetrahydro-1H, 5H-benzo [i,j]quinolizin-9-yl)methylene]- <IMAGE>

What is claimed is: 
     
       1. A photosensitive composition comprising: (a) a compound of the formula: ##STR4##   wherein p and q independently are 0 or 1 and r, m and n independently are 2 or 3; and R 1 , R 2 , R 3  and R 4 , independently are selected from the group consisting essentially of hydrogen and alkyl having 1 to 4 carbon atoms or alkoxy having 1 to 4 carbon atoms.   (b) an ethylenically unsaturated compound capable of free radical generated addition polymerization,   (c) a free radical generating initiation system activated by actinic radiation.   
     
     
       2. Composition of claim 1 present as a liquid. 
     
     
       3. The composition of claim 1 present as a dry film. 
     
     
       4. The composition of claim 1 wherein p and q are 0, m and n are 3, r is 2 and R 1 , R 2 , R 3  and R 4  are hydrogen. 
     
     
       5. The composition of claim 1 wherein said initiation system comprises a HABI and a chain transfer 
     
     
       6. A photosensitive composition comprising: (a) a compound of the formula: ##STR5##   wherein p and q independently are 0 or 1 and r, m and n independently are 2 or 3; and R 1 , R 2 , R 3  and R 4 , independently are selected from the group consisting of hydrogen and alkyl having 1 to 4 carbon atoms or alkoxy having 1 to 4 carbon atoms,   (b) an ethylenically unsaturated compound capable of free radical generated addition polymerization,   (c) a free radical generating initiation, system activated by actinic radiation,   (d) a polymeric material.   
     
     
       7. The composition of claim 6 wherein p and q are 0, m and n are 3, r is 2 and R 1 , R 2 , R 3  and R 4  are hydrogen. 
     
     
       8. A process for forming a photoresist on a substrate comprising the steps of: (a) applying to the substrate a photosensitive composition,   (b) imagewise exposing the composition to actinic radiation,   (c) removing unexposed areas of the composition to form resist areas,   (d) permanently modifying areas of the substrate which are unprotected by the resist areas by etching the substrate or by depositing a material onto the substrate,   wherein the photosensitive composition comprises: (i) a compound of the formula: ##STR6##   wherein p and q independently are 0 or 1 and r, m and n independently are 2 or 3; and R 1 , R 2 , R 3  and R 4 , independently are selected from the group consisting of hydrogen and alkyl having 1 to 4 carbon atoms or alkoxy having 1 to 4 carbon atoms,   (ii) an ethylenically unsaturated compound capable of free radical generated addition polymerization,   (iii) a free radical generating initiation system activated by actinic radiation.     
     
     
       9. The process of claim 8 wherein the resist areas are removed from the substrate after step (d). 
     
     
       10. The process of claim 8 wherein p and q are 0, m and n are 3, r is 2 and R 1 , R 2 , R 3  and R 4  are hydrogen. 
     
     
       11. A single step process for forming a lightstable hologram which comprises exposing to modulated actinic radiation bearing holographic information a photopolymerizable layer comprising: (a) a compound of the formula: ##STR7##   wherein p and q independently are 0 or 1 and r, m and n independently are 2 or 3; and R 1 , R 2 , R 3  and R 4 , independently are selected from the group consisting of hydrogen and alkyl having 1 to 4 carbon atoms or alkoxy having 1 to 4 carbon atoms,   (b) a solvent soluble, thermoplastic polymeric binder,   (c) at least one liquid ethylenically unsaturated monomer capable of addition polymerization and having a boiling point above 100° C., and   (d) a free radical generating system activatable by actinic radiation.   
     
     
       12. The process of claim 11 wherein the modulated actinic radiation of a reference beam and an object beam enter on the same side of the photopolymerizable layer to form a transmission hologram. 
     
     
       13. The process of claim 11 wherein the modulated actinic radiation of a reference beam and an object beam enter on the opposite sides of the photopolymerizable layer to form a reflection hologram. 
     
     
       14. The process of claim 13 wherein the coherent radiation of a reference beam which is transmitted through the photopolymerizable layer to illuminate an object and generates an object beam by reflection back through the photopolymerizable layer. 
     
     
       15. The process of claim 11 wherein said free radical generating system activatable by actinic radiation comprises a HABI and a chain transfer agent. 
     
     
       16. The process of claim 15 wherein either said binder or said ethylenically unsaturated monomer contains a substituent selected from the group consisting of phenyl, phenoxy, naphthyl, naphthyloxy, heteroaromatic containing up to three aromatic rings, chlorine, bromine, and mixtures thereof, and the other constituent is substantially free of said substituent. 
     
     
       17. The process of claim 15 wherein said ethylenically unsaturated monomer contains a substituent selected from the group consisting of phenyl, phenoxy, naphthyl, naphthyloxy, heteroaromatic containing up to three aromatic rings, chlorine, bromine, and mixtures thereof, and the binder is substantially free of said substituent. 
     
     
       18. The process of claim 17 in which a solid ethylenically unsaturated monomer is also present. 
     
     
       19. The process of claim 18 wherein said solid ethylenically unsaturated monomer is N-vinyl carbazole. 
     
     
       20. The process of claim 19 wherein p and q are 0, m and n are 3, r is 2, and R 1 , R 2 , R 3  and R 4  are hydrogen.